SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed514394eb684de65d460d3392ba7fab42dd7aa7539e2e27238a17c4dce9d131' 
  AND token = '7XutMRCmOvxF44F7+X9CZ6fiTXrKBGSeYBJ/vUY/UVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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