SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0e14cf4c02abad4340decb98ec710bc72b8588236cbecbad63bf0a2ac032183' 
  AND token = 'kyJqQSBchxylY81EJMzAf8c+KGRihu0l9qrmfv2gUuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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