SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0e74537146132a4fdd25138d83abea219e0c8a54c6375d9037b9319ed1df0467' 
  AND token = 'vrTim8Soc9t2G51y3rJhwqduIbJKG7PUP7OGQtCQ268=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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