SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0b32255047ee127f527c99c874951a5794aa665361208fc8b761d79eda4c3fa' 
  AND token = 'rVzWxyEEcENb/kC1ZAZaAFnBZ7kiZYSDYR1ZWsH/bkc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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