SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a4b8aac00594ac1602e678a82d97677d9bc31b585224978779f7b1d5c716c5e' 
  AND token = 'hVLY8o/VQJsDEiwLZKGObc95Cq5i6XKpQXZfMsw/M/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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