SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5bef3d7d13e19917aeec63c9292c9e63a9f31af64f6de0da0824cfeac22c732' 
  AND token = 'j/u14JQMVH0/qANu7WNWPKabZxVGps51KxWXs1sBnOc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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