SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ca1b9e69692953bd5f5e6177550735b8b681ae39b5e1fc66379aa25e17147c06' 
  AND token = 'x+1l5MmRhBYGo+hFdKWHIE0Wczw5mH8PwbTyjNpp/LQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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