SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0bffa5d5a8dc49885072bebd8c754569e1aac2c6c7b77449bfbb38d5a5804ee2' 
  AND token = 'xUAXM50x4nd5b6KL71whV8dzXwHTLu5ngkhJbESWysc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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