SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2de0f411a0d68492ba7e2ff3287f4a25182e89504ad64e50e5df47ba2436ffeb' 
  AND token = 'Np9WKNqREHlI2pGocayN0ncXHz4tqi/tkiv6M4Yw3bg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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