SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9bf25e44440085060b5e4f56ce5541c155b0df8ffed73c9d15cdd63ba2bd4e2' 
  AND token = 'n7rSBr4PtX0nNMAWqQay07i4KX35Q0jS3L48tuCLz7E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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