SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c0081f2f8722c659c93ea856bda5f4eb9e0c3a42181b6d5c0924a39f7816be4' 
  AND token = 'mcW039lhJXYKw9hfYNjnc9l4jrpmPWyg4VqaRtswm/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}