SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '372706f33c55bb40262535d1b981d346ffb186ce8fb9cb39fa19a9177835ebc2' 
  AND token = 'DFP8yRLHN29okbp5NfG07JtodB9EqnZUi16/ErLKmB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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