SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '73bf5420caa75c145e672056bbd129f1d0997268392947470e47f672e1c6c9f6' 
  AND token = 'gUZqtG5FYLc1OYUSO3Jt5lcLTsczZ0mTcCMmdoary6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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