SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f2236247a1bde0a3c870422702dfc59648d5a60c787b3c90a8eaf3a9fa00d5f' 
  AND token = 'zZUhMqZZ+N0+Er8UXMLpVRX7jXKQ81gzYWesQPmCtMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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