SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'effc7efaa2027a14583d4cb25f97c8047d72657d2b2751ca22a2f7acdb27c51b' 
  AND token = 'Zh7SKB38t09FMG7FUNKfRaFtdzfOEV6kmlIskLHyF2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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