SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7301d3e06a96c8a69304d72a2772969eff5c7859f225b5aaf97c8a9fcd46ff1a' 
  AND token = 'nZugPPYynCiAFR7sCwor0rShJ+3tHnQnRjAGNYcx+y8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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