SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6b2d9aa0a9de0e5030ffa9c09cebcc10b71445f2b11b0100723891e942987718' 
  AND token = 'qCvcsZNm5vSIeEkT6OYfSg7O83YAoxB/VDEKn5JZ6iM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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