SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1106e4a8656d2353c5db598f16fee0a270f912ad4a2c72af657ef7f9b9c357c' 
  AND token = 'Va608Of2HT3FdrpO0UxKXoBU6cLYcT2/eELaedM3E10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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