SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ee336099b8a60be91fdab049fe1e5dea15b587ae05db5e2df34f8831b22dba7' 
  AND token = 'HVf6jrW3S0/ZRRMDQRNFaEtqnYcXbzHnKr3F4eqTv58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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