SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06c1681a1c81f7b87983e4b7790b46bebb2e56fae73225a9ae83eeee1ba921c1' 
  AND token = 'hkkNNDYQOdX6vDZRffyaDzxkbH3Hn+Jmte9HpTAkgcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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