SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4b93ee72a1c6b485f29c123ed7d54367b3729ec5d803bb9f96741abc5e796cf' 
  AND token = '9YWuG7MqsdOH07GSWlhKtLq0IlEdZjVRW9q6835z/Bo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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