SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11a214a4ff2198b564fba95bb6169053457cf4d8a0d6686cd9a58a16a009d8d4' 
  AND token = 'IITFbHwHMd5D0oapLlMw75q20lR1zJtBiN/IN/BdwxI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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