SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a627dccaeee95cd24d7b4a982760571355535fc612358ba6fb349e4a6ba6320' 
  AND token = 'If49Bv9eiszrqHJEoYeX1Xg/UFHQ0CLnHGBJcSbogE4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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