SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8596d9f2aba5f40afe40f99d736528431deb089139ecaf9c820ba4b758462a9' 
  AND token = 'GmjDNWc4ZJKxF7yM2at47U4JAJLBdH4caJuypnMb0Jc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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