SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e47277019ac06816e4c16f2fad79e21135b02725a811a11c8099cfe45bc6057a' 
  AND token = '+2OcX9rgi7ZE1geVKRfzhBZxcnqobtp3m+vM4pCPghU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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