SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02999b2f3f5c04f150252a6f5dd58c330e02d80b0d81a6b7c44961458050edbd' 
  AND token = '2jZoqj8OLNmU3BkcOgo3+x901oEkZLXJUpxCBrqSpVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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