SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '13a6fb7d43716ee4f215342426a378bea00cf2c024ffdc65a31d4651e5b4990d' 
  AND token = '55iBdg1GCUmrIaHLqR8B69YW5bAvES4KsO7I9VERmBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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