SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811ade2a8316bde7d5748c63df44d7b321ec8faf3f24db67a1ca524926818b02' 
  AND token = 'ft7s+yB3nzjHsJlUcr88GqoljVoT6crgzv4YvTL5Jt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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