SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '212c0a2b5da279f8917199d6f18e989de550d84b3de1f8bace1fcf4dfd364632' 
  AND token = 'FeA09RcAlCQz7NaSYAhNWqduo9Tn97PMGvGqBLnsAug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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