SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4137801ee42cb769c4db187aa70502ad92b002a9eb2492ea2c4f12c53a5aed9b' 
  AND token = '6Hjb1k6YB0lxGxusEAwdkfD0Sb51gBJ9rbo7diEPWaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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