SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5cd2934cfaa5d8def3a7a603fb05b9aeea17e0ba3ca3380d83a714ee89fedc01' 
  AND token = 'azKcExy2yRLI6ph4AwBiEEk31mlyA5LQdako1xiGi0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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