SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e64604faea52a836e17fd550dd469025a42193788ebaea2c8c5dc953bf670f1' 
  AND token = 'V1x6x3t4USaWprZc3bud5TEHsfyqWMeFYmmyrgfU+DQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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