SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1a35564b2536438de5c83658238f7f5a3403f5471dedf539621693792c2c6ba' 
  AND token = 'KnRDtnZTGC/SRVCnBNNN2K7NXckoNkqTCHmt649trss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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