SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61cb076671e7bbfbd3fc39bcfee427f2dbd0a338875fe9dc2fdbd1939ad40987' 
  AND token = 'lliqM/aAM+4rEuhTgDunQhFcWYWUzkH+LZG8nL/dXnc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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