SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '936ab2c9c6e5e64c3708ce9134d7b46255e13c13ad031937ffb20af71d75e5be' 
  AND token = 'AqbSFJO8HBkavlLE0wNedDHpbVizlHs/hZseFHMeEjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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