SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e31e781f4ab115a64ca5f1822a1fdb6e218c659ef5061905a514f70f26f30d4d' 
  AND token = 'CELXGdvsmVzxnshWFfklVbn3TbLoENCxgtZhZeCgXB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}