SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '010279c020861faad47ebd3b8103990d632bff7c0eb34ec1febb3da92094557a' 
  AND token = 'J7fqHbbvZzgSqJmaU+P7jv3mYHsL7Ni3p+v86/1wst4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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