SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '295c3a437cba3e9e707c1fcbc6007062de96e7def13eb5002fe790701e3a5e94' 
  AND token = 'Rw/LxY4peuHqoYUOoK89LPE6ZYgvTunVFVelgDxZKmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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