SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7eeb2cc0b394805d472acd5dd71a6bd43eaf936a278af01d97cfd3fe88d5fc1' 
  AND token = 'sWBnXSKSfU37Z2+qj7SGY0x6IGCc+TDM2NR1aPATLog=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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