SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba90f9780c1a60b0468a529715b632e62385e9da348a8208aac4c3fdee852323' 
  AND token = 'zsNfMaynm0uTQVHkErjTC9zdBPS9W4S4f3mVD1xc/4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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