SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1079d579961d466dad2645a459826979dccfadeedbcb4a69151d33a8e7d97509' 
  AND token = 'rH/JjXNkborw6Ksdczqgkig/C2VN+9E5fOh5vzgAi6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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