SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b88927c86cecb8ed24d10da2fe5446341d3d87fee92aa32e6dfff32bb5f6f2e1' 
  AND token = 'ilXTfYFc8Iu8YvMw/2fDPs63z6UepQrgLMjUzX/24VY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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