SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74c2491063280e36d79042dac43705f977f5c60b7841908b970d6febc662bdbc' 
  AND token = '9avSQYxA3QeXEqtHrBC/7kRG7acaaJ/7gF873/9CyvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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