SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94dbbe9fcdace50f10f2865cb4073a7fe8eab9da403ee8af96798ad9dbcaafa7' 
  AND token = 'Q9X6BvwYcoukLfQuXtDcImZ5fFEqT3TBFM+2lJ5CRbw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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