SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7309b100b14835a73147cf7072ea9c6e2b1fca46bd4364bac51d978ca3dcf5d8' 
  AND token = 'ebBpqYZYsEeZrGmGjPStrLNgh+xNoZNHZVrv2prweCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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