SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e85f9500662107763449b755418f2fae9fbb9ddecd41d507e94fdee88049e0fd' 
  AND token = 'GBH1fV7o4e5m1sGUVMaSF+d+p6PRNS6rPSsaomiLEgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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