SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65984d34f871ebe0c82ec695bfaec102ab2775d307118bfc954c5a4d9d80ec4d' 
  AND token = '+KZG7+YyZVRVP6e/9oAHSPu9Fc2WYkPI03TPFC1J9qI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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