SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8b3ca20cec29b7c4c7dd630930959bbe96f8bd3bf7c16b8881ad2bd38c5ffeb4' 
  AND token = '6Jdawq7MzcRUgD1DH/o6N/ggTXq7Ya5b9aOvTQOHF7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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