SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '530ec4c6da020aa48b834420878fdea025b93f6b4b4264d2e94023951775c345' 
  AND token = 'ovVmzrIVW85rHUs7oWp0Y7QleMCNs9bQgEMazQ7nDHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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