SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ed384a97c570faaa82e31edb8f90fa7786b7fecdb5fffb849fa796b39bbbb0a' 
  AND token = 'AzHGfKHFpxk5v7+Ys2+AxRpHlrXwwOwZWLdmcqn7CLg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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