SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '26fb13acd1443f5a1cbee70f66b514bcd438a243d8a50be31970807a2c860179' 
  AND token = 'qQ51/09XITK5ujV/YCd8aPQVJ/deTKW+V7vu2fMyC9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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