SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b772aaed36ae903447cdc342dc083d9e4f001de727d9bf77e120fff1ebcbbcea' 
  AND token = 'aIY0gUDkA5mSnvi0NFro3ahhuS38F7iZhdI2RBLIOuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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