SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa5183b255b05604ce9b32b8330cbda3db879b0ccdf1a85819cbfd01c34763ec' 
  AND token = 'snudOvRCDgXuy1wJfbZvEt42hhvlDrzMoT/iXd1ZxvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00076

JSON explain

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