SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4f4dcdd4f9bef2c13616a077f564eab64d688e3c7d69fa49bb9aa2eac14624e' 
  AND token = 'sbM7OQPZVJQldTaZifYODM3A4vIyfo2tUIby53EumOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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