SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74fd158965f6e5330e5ec2c25245a37d707868f657595385ed527cd56b31dfd9' 
  AND token = 'jJRPjaZTYXMweYZvARhwbhzHsNeRecCz02ZEq5I7WGo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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