SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d98f1aaf525332564a47159d9cf7991d27210d68f186cbddefec7a16426ed5e' 
  AND token = 'EoqTcGkx7Gy2AHuizoCITYCO5/2/+2lwKWCNeOlSw5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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