SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77dbca2dffaf3171a990c248326bcd4252d978ea2c79d6f974e863673305a58c' 
  AND token = 'vUdVctgKpGKmSNA7lNCD0CuCCzVhfZwluMp2cy0lztY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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