SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4086d6b5811c807c507389974fe9ba445cf4b0aea83cd59b78487db18c77710f' 
  AND token = 'dnwnqsmOTOiTVBWzXaLLx4ddze+fVoxvn0LqlDfXIJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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