SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8130c6dd42f3f767cade3c93d35f63a14a7a5655dcb521662a1edfb1745eed46' 
  AND token = 'PIC61xYaNA0uoMdtWkGS4bQO26wymD70EKOTRjyHzfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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