SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '451ab53b02a3a812d90e03157431946e67c763eaab542f3b5b77b4a531566039' 
  AND token = 'Y+unKCouQX/zYvOZWn1wHzFSsVECa3fjimHTjZP3qJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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