SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '372e0da7e876d523a609e796d4df28b2edc60a3567558fcaee25acdb2889de9a' 
  AND token = 'y9EUqypJXGguWVIjKvw1Pb1t3QfOM+wIxiZLX+fdnm4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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