SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bad33ec8d44dce734f0fdc19b623de7cd9988ed4897ff21ea803f020979d3f02' 
  AND token = 'za9XbwkDq2efZD2v8rXrxGPMVgwEozgbOoXrXAO9l90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}