SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4477eaa9a1afd445f3bec86d2e3a745ace0bfba0822c1964d54fb12367fb9626' 
  AND token = 'wfhYJrpPHnYQy6EUFv/pqXcfDnrhb8drfrOe8HtWt+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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