SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c058ed738ed4a3b626ff8a089ba02e342741e6f45dfbf504ea09f4bdce7856c4' 
  AND token = '1+7QBVVih8kwijw3UsnvGjQazqHx1d1nzHjx9AMmATc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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