SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2a362f1bd8ac7c0cc27d34b84da7df1809054a15b5a07a117fa290ab3a04e95' 
  AND token = 'qwCELjUshBHIubBTJREqhvUZrBOvzEoDW7Z2+87OoqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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