SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64bd7461d9f9f52ee680a378680cb0ed9597c028f99682bb63c81904b66a4521' 
  AND token = 'vTkIofuudYksa2L/+Spl2dB7+z3HE8/MHqdnrzr6nVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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