SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eacc336844fb02511e370fa90612035fb2792517598cf68ffd57717853eda811' 
  AND token = 'P6oLmfpGe+i/53QjcSDzZJT5Lk3iz+dLjSv9H0P9XZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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