SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '183088738ff58918e997f5c677704a97302b936d38397fba516e5dc15558e5e7' 
  AND token = 'VKnqCTcmzcATxfgd8xvXjxOKmwdLX4jbcQa7WK4if5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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