SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '196c1269298f3ca004acfdec097587e5f4fb821bca058edf6a134871012188d6' 
  AND token = 'AuotDllazd8jzdnaC//Bw5LCqxhuYDK6E+AihCnCbxA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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