SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c59fa819f784ba8b19c4b10c583b65f96c15c9871fce02123f3d6e1b45f1006d' 
  AND token = 'dZYxhmN+ol8t0EzPCQ/Kj7+oa/MZNz1AD6qVfTrGFNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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