SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09ec71774201b2977cd9e09139f40137e2ba10426adf0949e015bca62a155812' 
  AND token = 'XUacKSqn86+HLeVmkVBizsjaa8MRKH3tZgvuPurZosE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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