SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b67a0dd893f7cb08f11b1c357e78f4245111ec69cb9f9b0b9678e7ac6dd7f39' 
  AND token = 'BlCYZIpJAznyzp+yrOU29vbxFxJ/L/SuDwFLbM1IIAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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