SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '93f8fed0a92d6149edc4433a9365dc6b27cdd90c16a2c077e50429769b8d9c28' 
  AND token = 'GXP0gLO1MXZpeFfvm8n1WE/vLd36Y7lLV86dhWdPJTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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