SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa109201dfcac23c19f8435f95e41eaf7559e8c4e68ca6e7829f057da19046b7' 
  AND token = 'UBO/r2o3D1Zh3LY4neB2PnZ/+cCbXDLs6K7RTUqlSXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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