Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '861b95620c8282fe2e33d3ce9cc95ccebe17cc71bf95dfeebe7e9edf7971b2f1' 
  AND token = 'CUlOvVVZ1DQSyQZ6LZ3Hav0gr+aj+ti/Dk3ejWkHCSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}