SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd25901997f9ced6e04bddc0e74f19f3ad036331e579f099dc03c1c9ba8cb7ce1' 
  AND token = 'dxAFfFn7gp0BrSGN4owPiSKyA6EIvNzkBsYbHDa/HjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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