SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55a3015e7dd680265ab6e465967acd0b0bd789659fa5a000481418ae5685b9bc' 
  AND token = 'HrECT2VNabjNQNWGO5MFBYAnfTTPA+pmWgTdHaHOJY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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