SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ad9e229ebc870d96d3ceb8bd043df96c8ab5f382d82259baad7914bacb5920a' 
  AND token = 'eYh9osUgIJ9JhT+dHrdxsNkJioEJ7MlcwpRNivozwdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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