SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0259026597438ac844bbb04afb794e5ec41cfa1ee6503bbbe84e45fa57780a6d' 
  AND token = 'UIw2tjXSnGjhWE6X4dhhTzJ05W/ppuowngiufzxJOCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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