SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96065f287fc8e4510ea29e31e2e6647abe32d321c2d86daf9089f76fd169c5f4' 
  AND token = '+5xHUx9iNVMcZ+1ydKvvGr2oWjjoDuuPFLOqGCZardY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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