SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db0c690e96e9fd8382bca7ffc88d0bfab30e51088e4bbe583c9efd8a2055b23a' 
  AND token = 'p5rlgSrnyffvDh22GIluKD5lQzgg9OZbH+2Y19H8nv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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