SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0981835212d1635e2af62e3aa4b81ad6fafc064110e433d585b488d39a297958' 
  AND token = 'utwzGY9DisKY/WYxZwPwRJcKDohlapIX6efCJimwW1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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