SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0282323864cac495802917ccea65086f79c3686931dd489c0e425e2c5aec4f35' 
  AND token = 'CXYrtGIaAsiYIkfA5RLe6yvRLbZ0L8OEIHzljXsN2f0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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