SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cb156dbff2d43728d4aab97c50af90c913b691bc0a59017e839dd78aa05b6b09' 
  AND token = 'tJR64GlpiWZjw2cUn16CgLmGBqd8kolra4/MsPeSv4E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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