SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3079322d897caf8328bbbbf7a446df6f2173cba567b729c54f5a99abc707130d' 
  AND token = 'yX+KrqpuKcS+IzzDcbrBwc+CzccHmJFIKWMaCC6QUds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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